package com.gszkc.aspect;

import com.gszkc.annotation.AutoFill;
import com.gszkc.constant.AutoFillConstant;
import com.gszkc.context.BaseContext;
import com.gszkc.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.time.LocalDateTime;

/**
 * 自定义切面类，实现公有字段自动填充
 */
@Component
@Slf4j
@Aspect
public class AutoFillAspect {

    /**
     * 切入点
     */
    @Pointcut("execution(* com.gszkc.mapper.*.*(..)) && @annotation(com.gszkc.annotation.AutoFill)")
    public void autoFillPointCut(){}

    /**
     *
     */
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint)  {
        log.info("AOP开始进行填充");
        //获取拦截的方法上数据库操作类型
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        AutoFill annotation = signature.getMethod().getAnnotation(AutoFill.class);
        OperationType operationType = annotation.value();
        //获取拦截的方法上参数--实体对象
        Object[] args = joinPoint.getArgs();
        if (args == null || args.length == 0){
            return;
        }
        Object entity = args[0];
        //准备公有字段的添加数据
        LocalDateTime now = LocalDateTime.now();
        Long currentId = BaseContext.getCurrentId();
        //根据操作类型进行不同的赋值
        if (operationType == OperationType.INSERT){
            //4个公有字段
            try {
                Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
                Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
                //通过反射为属性赋值
                setCreateTime.invoke(entity,now);
                setCreateUser.invoke(entity,currentId);
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }

        }else if (operationType == OperationType.UPDATE){
            //2个公有字段
            try {
                Method setUpdateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
                Method setUpdateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
                //通过反射为属性赋值
                setUpdateTime.invoke(entity,now);
                setUpdateUser.invoke(entity,currentId);
            } catch (Exception e) {
                throw new RuntimeException(e);
            }
        }
    }

}
